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Staszkiewicz R, Gralewski M, Gładysz D, Bryś K, Garczarek M, Gadzieliński M, Marcol W, Sobański D, Grabarek BO, sobaÅ Ski D, Grabarek BO. Evaluation of the concentration of growth associated protein-43 and glial cell-derived neurotrophic factor in degenerated intervertebral discs of the lumbosacral region of the spine. Mol Pain 2023; 19:17448069231158287. [PMID: 36733259 PMCID: PMC10071099 DOI: 10.1177/17448069231158287] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Important neurotrophic factors that are potentially involved in degenerative intervertebral disc (IVD) disease of the spine's lumbosacral (L/S) region include glial cell-derived neurotrophic factor (GDNF) and growth associated protein 43 (GAP-43). The aim of this study was to determine and compare the concentrations of GAP-43 and GDNF in degenerated and healthy IVDs and to quantify and compare the GAP-43-positive and GDNF-positive nerve fibers. The study group consisted of 113 Caucasian patients with symptomatic lumbosacral discopathy (confirmed by a specialist surgeon), an indication for surgical treatment. The control group included 81 people who underwent postmortem examination. GAP-43 and GDNF concentrations were significantly higher in IVD samples from the study group compared with the control group, and the highest concentrations were observed in the degenerated IVDs that were graded 4 on the Pfirrmann scale. In the case of GAP-43, it was found that as the degree of IVD degeneration increased, the number of GAP-43-positive nerve fibers decreased. In the case of GDNF, the greatest number of fibers per mm2 of surface area was found in the IVD samples graded 3 on the Pfirrmann scale, and the number was found to be lower in samples graded 4 and 5. Hence, GAP-43 and GDNF are promising targets for analgesic treatment of degenerative IVD disease of the lumbosacral region of the spine.
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Affiliation(s)
- Rafał Staszkiewicz
- Department of Neurosurgery, 5th Military Clinical Hospital with the SP ZOZ Polyclinic in Krakow, Kraków, Poland.,Department of Histology, Cytophysiology, and Embryology, Faculty of Medicine in Zabrze, Academy of Silesia Zabrze, Poland
| | - Marcin Gralewski
- Department of Neurosurgery, 5th Military Clinical Hospital with the SP ZOZ Polyclinic in Krakow, Kraków, Poland.,Department of Histology, Cytophysiology, and Embryology, Faculty of Medicine in Zabrze, Academy of Silesia Zabrze, Poland
| | - Dorian Gładysz
- Department of Neurosurgery, 5th Military Clinical Hospital with the SP ZOZ Polyclinic in Krakow, Kraków, Poland.,Department of Histology, Cytophysiology, and Embryology, Faculty of Medicine in Zabrze, Academy of Silesia Zabrze, Poland
| | - Kamil Bryś
- Department of Histology, Cytophysiology, and Embryology, Faculty of Medicine in Zabrze, Academy of Silesia Zabrze, Poland
| | - Michał Garczarek
- Department of Neurosurgery, 5th Military Clinical Hospital with the SP ZOZ Polyclinic in Krakow, Kraków, Poland
| | - Marcin Gadzieliński
- Department of Neurosurgery, 5th Military Clinical Hospital with the SP ZOZ Polyclinic in Krakow, Kraków, Poland
| | - Wiesław Marcol
- Department of Physiology, School of Medicine in Katowice, 49613Medical University of Silesia, Katowice, Poland.,Department of Neurosurgery, Provincial Specialist Hospital No. 2 in Jastrzębie - Zdrój, Jastrzębie-Zdrój, Poland
| | - Dawid Sobański
- Department of Histology, Cytophysiology, and Embryology, Faculty of Medicine in Zabrze, Academy of Silesia Zabrze, Poland.,Department of Neurosurgery, Szpital sw Rafala w Krakowie, Krakow, Poland
| | - Beniamin Oskar Grabarek
- Department of Neurosurgery, 5th Military Clinical Hospital with the SP ZOZ Polyclinic in Krakow, Kraków, Poland.,Department of Histology, Cytophysiology, and Embryology, Faculty of Medicine in Zabrze, Academy of Silesia Zabrze, Poland
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Yuan ZL, Liu XD, Zhang ZX, Li S, Tian Y, Xi K, Cai J, Yang XM, Liu M, Xing GG. Activation of GDNF-ERK-Runx1 signaling contributes to P2X3R gene transcription and bone cancer pain. iScience 2022; 25:104936. [PMID: 36072549 PMCID: PMC9441333 DOI: 10.1016/j.isci.2022.104936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 07/15/2022] [Accepted: 08/10/2022] [Indexed: 11/24/2022] Open
Abstract
Bone cancer pain is a common symptom in cancer patients with bone metastases and its underlying mechanisms remain unknown. Here, we report that Runx1 directly upregulates the transcriptional activity of P2X3 receptor (P2X3R) gene promoter in PC12 cells. Knocking down Runx1 in dorsal root ganglion (DRG) neurons suppresses the functional upregulation of P2X3R, attenuates neuronal hyperexcitability and pain hypersensitivity in tumor-bearing rats, whereas overexpressing Runx1 promotes P2X3R gene transcription in DRG neurons, induces neuronal hyperexcitability and pain hypersensitivity in naïve rats. Activation of GDNF-GFRα1-Ret-ERK signaling is required for Runx1-mediated P2X3R gene transcription in DRG neurons, and contributes to neuronal hyperexcitability and pain hypersensitivity in tumor-bearing rats. These findings indicate that the Runx1-mediated P2X3R gene transcription resulted from activation of GDNF-GFRα1-Ret-ERK signaling contributes to the sensitization of DRG neurons and pathogenesis of bone cancer pain. Our findings identify a potentially targetable mechanism that may cause bone metastasis-associated pain in cancer patients. Runx1 directly upregulates the transcriptional activity of P2X3R gene promoter Upregulation of Runx1-mediated P2X3R gene transcription underlies bone cancer pain Involvement of GDNF-Ret-ERK signaling in Runx1-mediated P2X3R gene transcription
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Ferrini F, Salio C, Boggio EM, Merighi A. Interplay of BDNF and GDNF in the Mature Spinal Somatosensory System and Its Potential Therapeutic Relevance. Curr Neuropharmacol 2021; 19:1225-1245. [PMID: 33200712 PMCID: PMC8719296 DOI: 10.2174/1570159x18666201116143422] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 09/17/2020] [Accepted: 10/05/2020] [Indexed: 11/22/2022] Open
Abstract
The growth factors BDNF and GDNF are gaining more and more attention as modulators of synaptic transmission in the mature central nervous system (CNS). The two molecules undergo a regulated secretion in neurons and may be anterogradely transported to terminals where they can positively or negatively modulate fast synaptic transmission. There is today a wide consensus on the role of BDNF as a pro-nociceptive modulator, as the neurotrophin has an important part in the initiation and maintenance of inflammatory, chronic, and/or neuropathic pain at the peripheral and central level. At the spinal level, BDNF intervenes in the regulation of chloride equilibrium potential, decreases the excitatory synaptic drive to inhibitory neurons, with complex changes in GABAergic/glycinergic synaptic transmission, and increases excitatory transmission in the superficial dorsal horn. Differently from BDNF, the role of GDNF still remains to be unraveled in full. This review resumes the current literature on the interplay between BDNF and GDNF in the regulation of nociceptive neurotransmission in the superficial dorsal horn of the spinal cord. We will first discuss the circuitries involved in such a regulation, as well as the reciprocal interactions between the two factors in nociceptive pathways. The development of small molecules specifically targeting BDNF, GDNF and/or downstream effectors is opening new perspectives for investigating these neurotrophic factors as modulators of nociceptive transmission and chronic pain. Therefore, we will finally consider the molecules of (potential) pharmacological relevance for tackling normal and pathological pain.
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Affiliation(s)
- Francesco Ferrini
- Department of Veterinary Sciences, University of Turin, Grugliasco, Italy
- Department of Psychiatry & Neuroscience, Université Laval, Québec, Canada
| | - Chiara Salio
- Department of Veterinary Sciences, University of Turin, Grugliasco, Italy
| | - Elena M. Boggio
- Department of Veterinary Sciences, University of Turin, Grugliasco, Italy
| | - Adalberto Merighi
- Department of Veterinary Sciences, University of Turin, Grugliasco, Italy
- National Institute of Neuroscience, Grugliasco, Italy
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Mahato AK, Sidorova YA. Glial cell line-derived neurotrophic factors (GFLs) and small molecules targeting RET receptor for the treatment of pain and Parkinson's disease. Cell Tissue Res 2020; 382:147-160. [PMID: 32556722 PMCID: PMC7529621 DOI: 10.1007/s00441-020-03227-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 04/27/2020] [Indexed: 02/07/2023]
Abstract
Rearranged during transfection (RET), in complex with glial cell line-derived (GDNF) family receptor alpha (GFRα), is the canonical signaling receptor for GDNF family ligands (GFLs) expressed in both central and peripheral parts of the nervous system and also in non-neuronal tissues. RET-dependent signaling elicited by GFLs has an important role in the development, maintenance and survival of dopamine and sensory neurons. Both Parkinson's disease and neuropathic pain are devastating disorders without an available cure, and at the moment are only treated symptomatically. GFLs have been studied extensively in animal models of Parkinson's disease and neuropathic pain with remarkable outcomes. However, clinical trials with recombinant or viral vector-encoded GFL proteins have produced inconclusive results. GFL proteins are not drug-like; they have poor pharmacokinetic properties and activate multiple receptors. Targeting RET and/or GFRα with small molecules may resolve the problems associated with using GFLs as drugs and can result in the development of therapeutics for disease-modifying treatments against Parkinson's disease and neuropathic pain.
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Affiliation(s)
- Arun Kumar Mahato
- Institute of Biotechnology, HiLIFE, University of Helsinki, Viikinkaari 5D, 00014, Helsinki, Finland
| | - Yulia A Sidorova
- Institute of Biotechnology, HiLIFE, University of Helsinki, Viikinkaari 5D, 00014, Helsinki, Finland.
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The impact of N-cadherin–β-catenin signaling on the analgesic effects of glial cell-derived neurotrophic factor in neuropathic pain. Biochem Biophys Res Commun 2020; 522:463-470. [DOI: 10.1016/j.bbrc.2019.11.076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 11/13/2019] [Indexed: 12/27/2022]
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Genty J, Tetsi Nomigni M, Anton F, Hanesch U. The combination of postnatal maternal separation and social stress in young adulthood does not lead to enhanced inflammatory pain sensitivity and depression-related behavior in rats. PLoS One 2018; 13:e0202599. [PMID: 30142161 PMCID: PMC6108470 DOI: 10.1371/journal.pone.0202599] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 07/19/2018] [Indexed: 11/19/2022] Open
Abstract
The cumulative and match/mismatch hypotheses of stress are still under discussion regarding the effects of early life stress (ELS) on the vulnerability or resilience to psychopathology. In this context, an additional stress in later life (second hit) often leads to stress-related disorders that frequently include comorbid pain states. We previously observed that maternal separation (MS), a model of ELS, reduces vulnerability to neuropathic and inflammatory pain in rats. In the present study, we investigated the effects of an additional later stressor on the vulnerability to inflammatory pain. Sprague Dawley pups were divided into 4 groups: controls (CON, no stress), MS, social stress (SS) and MS+SS. At young adult age (from 7 to 15 weeks), stress- as well as pain-related parameters were evaluated prior and during 21 days following the induction of paw inflammation with complete Freund's adjuvant (CFA). Finally spinal glutamatergic transmission, immunocompetent cells, pro-inflammatory cytokines and growth factors were examined using qPCR. None of the stress conditions had a significant impact on corticosterone levels and anhedonia. In the forced swim test, MS and SS displayed increased passive coping whereas the combination of both stressors revoked this effect. The different stress conditions had no influence on basal mechanical thresholds and heat sensitivity. At 4 days post-inflammation all stress groups displayed lower mechanical thresholds than CON but the respective values were comparable at 7, 10, and 14 days. Only on day 21, MS rats were more sensitive to mechanical stimulation compared to the other groups. Regarding noxious heat sensitivity, MS+SS animals were significantly less sensitive than CON at 10 and 21 days after CFA-injection. qPCR results were mitigated. Despite the finding that stress conditions differentially affected different players of glutamatergic transmission, astrocyte activity and NGF expression, our biochemical results could not readily be related to the behavioral observations, precluding a congruent conclusion. The present results do neither confirm the cumulative nor corroborate or disprove the match/mismatch hypothesis.
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Affiliation(s)
- Julien Genty
- Research group Stress, Pain and Pain Modulation, Institute for Health and Behavior, University of Luxembourg, Luxembourg, Luxembourg
- * E-mail:
| | - Milène Tetsi Nomigni
- Research group Stress, Pain and Pain Modulation, Institute for Health and Behavior, University of Luxembourg, Luxembourg, Luxembourg
| | - Fernand Anton
- Research group Stress, Pain and Pain Modulation, Institute for Health and Behavior, University of Luxembourg, Luxembourg, Luxembourg
| | - Ulrike Hanesch
- Research group Stress, Pain and Pain Modulation, Institute for Health and Behavior, University of Luxembourg, Luxembourg, Luxembourg
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Ota H, Katanosaka K, Murase S, Furuyashiki T, Narumiya S, Mizumura K. EP2 receptor plays pivotal roles in generating mechanical hyperalgesia after lengthening contractions. Scand J Med Sci Sports 2017; 28:826-833. [DOI: 10.1111/sms.12954] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/26/2017] [Indexed: 11/26/2022]
Affiliation(s)
- H. Ota
- Department of Neuroscience II; Graduate School of Medicine; Nagoya University; Nagoya Japan
- Department of Judo Therapy; Faculty of Medical Technology; Teikyo University; Utsunomiya Japan
- Department of Physical Therapy; College of Life and Health Sciences; Chubu University; Kasugai Japan
| | - K. Katanosaka
- Department of Neuroscience II; Graduate School of Medicine; Nagoya University; Nagoya Japan
- Department of Biomedical Sciences; College of Life and Health Sciences; Chubu University; Kasugai Japan
| | - S. Murase
- Department of Neuroscience II; Graduate School of Medicine; Nagoya University; Nagoya Japan
- Department of Physical Therapy; College of Life and Health Sciences; Chubu University; Kasugai Japan
| | - T. Furuyashiki
- Department of Pharmacology; Graduate School of Medicine; Kyoto University; Kyoto Japan
| | - S. Narumiya
- Department of Pharmacology; Graduate School of Medicine; Kyoto University; Kyoto Japan
| | - K. Mizumura
- Department of Neuroscience II; Graduate School of Medicine; Nagoya University; Nagoya Japan
- Department of Physical Therapy; College of Life and Health Sciences; Chubu University; Kasugai Japan
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Ding Z, Xu W, Zhang J, Zou W, Guo Q, Huang C, Liu C, Zhong T, Zhang JM, Song Z. Normalizing GDNF expression in the spinal cord alleviates cutaneous hyperalgesia but not ongoing pain in a rat model of bone cancer pain. Int J Cancer 2016; 140:411-422. [PMID: 27716965 DOI: 10.1002/ijc.30438] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 08/23/2016] [Accepted: 09/14/2016] [Indexed: 12/12/2022]
Abstract
Bone cancer pain (BCP) is the most common complication in patients with bone cancer. Glial cell line-derived neurotrophic factor (GDNF) is believed to be involved in chronic pain conditions. In this article, the expression and roles of GDNF were studied in a rat model of BCP induced by tibia injection of Walker 256 rat mammary gland carcinoma cells. Significant mechanical and thermal hyperalgesia and ongoing pain were observed beginning as early as day 5 post injection. The expression level of GDNF protein examined on day 16 after tibia injection was decreased in the L3 dorsal root ganglion (DRG) and lumbar spinal cord, but not in other spinal levels or the anterior cingulate cortex. Phosphorylation of Ret, the receptor for GDNF family ligands, was also decreased. Furthermore, normalizing GDNF expression with lentiviral vector constructs in the spinal cord significantly reduced mechanical and thermal hyperalgesia, spinal glial activation, and pERK induction induced by tibia injection, but did not affect ongoing pain. Together these findings provide new evidence for the use of GDNF as a therapeutic treatment for bone cancer pain states.
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Affiliation(s)
- Zhuofeng Ding
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
| | - Wei Xu
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
| | - Jie Zhang
- Department of Anesthesiology, The Maternal and Child Health Hospital of Hunan Province, Changsha, People's Republic of China
| | - Wangyuan Zou
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
| | - Qulian Guo
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
| | - Changsheng Huang
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
| | - Chang Liu
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
| | - Tao Zhong
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
| | - Jun-Ming Zhang
- Pain Research Center, Department of Anesthesiology, University of Cincinnati, Cincinnati, Ohio
| | - Zongbin Song
- Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
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Gao YY, Hong XY, Wang HJ. Role of Nectin-1/c-Src Signaling in the Analgesic Effect of GDNF on a Rat Model of Chronic Constrictive Injury. J Mol Neurosci 2016; 60:258-66. [DOI: 10.1007/s12031-016-0792-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 06/30/2016] [Indexed: 12/20/2022]
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Ina K. A Case of Sigmoid Colon Cancer in which Somatic Pain was Rapidly Alleviated after Panitumumab Administration Despite Tumor Progression. ACTA ACUST UNITED AC 2016. [DOI: 10.6000/1927-7229.2016.05.01.5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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Fernandes ES, Russell FA, Alawi KM, Sand C, Liang L, Salamon R, Bodkin JV, Aubdool AA, Arno M, Gentry C, Smillie SJ, Bevan S, Keeble JE, Malcangio M, Brain SD. Environmental cold exposure increases blood flow and affects pain sensitivity in the knee joints of CFA-induced arthritic mice in a TRPA1-dependent manner. Arthritis Res Ther 2016; 18:7. [PMID: 26754745 PMCID: PMC4718045 DOI: 10.1186/s13075-015-0905-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 12/22/2015] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND The effect of cold temperature on arthritis symptoms is unclear. The aim of this study was to investigate how environmental cold affects pain and blood flow in mono-arthritic mice, and examine a role for transient receptor potential ankyrin 1 (TRPA1), a ligand-gated cation channel that can act as a cold sensor. METHODS Mono-arthritis was induced by unilateral intra-articular injection of complete Freund's adjuvant (CFA) in CD1 mice, and in mice either lacking TRPA1 (TRPA1 KO) or respective wildtypes (WT). Two weeks later, nociception and joint blood flow were measured following exposure to 10 °C (1 h) or room temperature (RT). Primary mechanical hyperalgesia in the knee was measured by pressure application apparatus; secondary mechanical hyperalgesia by automated von Frey system; thermal hyperalgesia by Hargreaves technique, and weight bearing by the incapacitance test. Joint blood flow was recorded by full-field laser perfusion imager (FLPI) and using clearance of (99m)Technetium. Blood flow was assessed after pretreatment with antagonists of either TRPA1 (HC-030031), substance P neurokinin 1 (NK1) receptors (SR140333) or calcitonin gene-related peptide (CGRP) (CGRP8-37). TRPA1, TAC-1 and CGRP mRNA levels were examined in dorsal root ganglia, synovial membrane and patellar cartilage samples. RESULTS Cold exposure caused bilateral primary mechanical hyperalgesia 2 weeks after CFA injection, in a TRPA1-dependent manner. In animals maintained at RT, clearance techniques and FLPI showed that CFA-treated joints exhibited lower blood flow than saline-treated joints. In cold-exposed animals, this reduction in blood flow disappears, and increased blood flow in the CFA-treated joint is observed using FLPI. Cold-induced increased blood flow in CFA-treated joints was blocked by HC-030031 and not observed in TRPA1 KOs. Cold exposure increased TRPA1 mRNA levels in patellar cartilage, whilst reducing it in synovial membranes from CFA-treated joints. CONCLUSIONS We provide evidence that environmental cold exposure enhances pain and increases blood flow in a mono-arthritis model. These changes are dependent on TRPA1. Thus, TRPA1 may act locally within the joint to influence blood flow via sensory nerves, in addition to its established nociceptive actions.
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Affiliation(s)
- Elizabeth S Fernandes
- Centre for Cardiovascular Excellence, Waterloo Campus, King's College London, Franklin-Wilkins Building, 150 Stamford St, London, SE1 9NH, UK. .,Programa de Pós-Graduação, Universidade Ceuma, São Luís, MA, 65075-120, Brazil.
| | - Fiona A Russell
- Centre for Cardiovascular Excellence, Waterloo Campus, King's College London, Franklin-Wilkins Building, 150 Stamford St, London, SE1 9NH, UK.
| | - Khadija M Alawi
- Centre for Cardiovascular Excellence, Waterloo Campus, King's College London, Franklin-Wilkins Building, 150 Stamford St, London, SE1 9NH, UK.
| | - Claire Sand
- Centre for Cardiovascular Excellence, Waterloo Campus, King's College London, Franklin-Wilkins Building, 150 Stamford St, London, SE1 9NH, UK.
| | - Lihuan Liang
- Centre for Cardiovascular Excellence, Waterloo Campus, King's College London, Franklin-Wilkins Building, 150 Stamford St, London, SE1 9NH, UK.
| | - Robin Salamon
- Centre for Cardiovascular Excellence, Waterloo Campus, King's College London, Franklin-Wilkins Building, 150 Stamford St, London, SE1 9NH, UK.
| | - Jennifer V Bodkin
- Centre for Cardiovascular Excellence, Waterloo Campus, King's College London, Franklin-Wilkins Building, 150 Stamford St, London, SE1 9NH, UK.
| | - Aisah A Aubdool
- Centre for Cardiovascular Excellence, Waterloo Campus, King's College London, Franklin-Wilkins Building, 150 Stamford St, London, SE1 9NH, UK.
| | - Matthew Arno
- Genomics Centre, Waterloo Campus, King's College London, Franklin-Wilkins Building, 150 Stamford St, London, SE1 9NH, UK.
| | - Clive Gentry
- Wolfson Centre for Age-Related Diseases, Guy's Campus, King's College London, London, SE1 1UL, UK.
| | - Sarah-Jane Smillie
- Centre for Cardiovascular Excellence, Waterloo Campus, King's College London, Franklin-Wilkins Building, 150 Stamford St, London, SE1 9NH, UK.
| | - Stuart Bevan
- Wolfson Centre for Age-Related Diseases, Guy's Campus, King's College London, London, SE1 1UL, UK.
| | - Julie E Keeble
- Institute of Pharmaceutical Science, Waterloo Campus, King's College London, Franklin-Wilkins Building, 150 Stamford St, London, SE1 9NH, UK.
| | - Marzia Malcangio
- Wolfson Centre for Age-Related Diseases, Guy's Campus, King's College London, London, SE1 1UL, UK.
| | - Susan D Brain
- Centre for Cardiovascular Excellence, Waterloo Campus, King's College London, Franklin-Wilkins Building, 150 Stamford St, London, SE1 9NH, UK.
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Merighi A. Targeting the glial-derived neurotrophic factor and related molecules for controlling normal and pathologic pain. Expert Opin Ther Targets 2015; 20:193-208. [PMID: 26863504 DOI: 10.1517/14728222.2016.1085972] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
INTRODUCTION Glial-derived neurotrophic factor (GDNF) and its family of ligands (GFLs) have several functions in the nervous system. As a survival factor for dopaminergic neurons, GDNF was used in clinical trials for Parkinson's disease. GFLs and their receptors are also potential targets for new pain-controlling drugs. Although molecules with analgesic activities in rodents mostly failed to be effective in translational studies, this potential should not be underestimated. AREAS COVERED The circuitry, molecular, and cellular mechanisms by which GFLs control nociception and their intervention in inflammatory and neuropathic pain are considered first. The problems related to effective GDNF delivery to the brain and the possibility to target the GFL receptor complex rather than its ligands are then discussed, also considering the use of non-peptidyl agonists. EXPERT OPINION In nociceptive pathways, an ideal drug should either: i) target the release of endogenous GFLs from large dense-cored vesicles (LGVs) by acting, for example, onto the phosphatidylinositol-3-phosphate [PtdIns(3)P] pool, which is sensitive to Ca(2+) modulation, or ii) target the GFL receptor complex. Besides XIB403, a tiol molecule that enhances GFRα family receptor signaling, existing drugs such as retinoic acid and amitriptyline should be considered for effective targeting of GDNF, at least in neuropathic pain. The approach of pain modeling in experimental animals is discussed.
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Affiliation(s)
- Adalberto Merighi
- a University of Turin, Department of Veterinary Sciences , Grugliasco, TO, Italy ;
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Presynaptic modulation of spinal nociceptive transmission by glial cell line-derived neurotrophic factor (GDNF). J Neurosci 2015; 34:13819-33. [PMID: 25297108 DOI: 10.1523/jneurosci.0808-14.2014] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The role of glial cell line-derived neurotrophic factor (GDNF) in nociceptive pathways is still controversial, as both pronociceptive and antinociceptive actions have been reported. To elucidate this role in the mouse, we performed combined structural and functional studies in vivo and in acute spinal cord slices where C-fiber activation was mimicked by capsaicin challenge. Nociceptors and their terminals in superficial dorsal horn (SDH; laminae I-II) constitute two separate subpopulations: the peptidergic CGRP/somatostatin+ cells expressing GDNF and the nonpeptidergic IB4+ neurons expressing the GFRα1-RET GDNF receptor complex. Ultrastructurally the dorsal part of inner lamina II (LIIid) harbors a mix of glomeruli that either display GDNF/somatostatin (GIb)-IR or GFRα1/IB4 labeling (GIa). LIIid thus represents the preferential site for ligand-receptor interactions. Functionally, endogenous GDNF released from peptidergic CGRP/somatostatin+ nociceptors upon capsaicin stimulation exert a tonic inhibitory control on the glutamate excitatory drive of SDH neurons as measured after ERK1/2 phosphorylation assay. Real-time Ca(2+) imaging and patch-clamp experiments with bath-applied GDNF (100 nM) confirm the presynaptic inhibition of SDH neurons after stimulation of capsaicin-sensitive, nociceptive primary afferent fibers. Accordingly, the reduction of the capsaicin-evoked [Ca(2+)]i rise and of the frequency of mEPSCs in SDH neurons is specifically abolished after enzymatic ablation of GFRα1. Therefore, GDNF released from peptidergic CGRP/somatostatin+ nociceptors acutely depresses neuronal transmission in SDH signaling to nonpeptidergic IB4+ nociceptors at glomeruli in LIIid. These observations are of potential pharmacological interest as they highlight a novel modality of cross talk between nociceptors that may be relevant for discrimination of pain modalities.
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Schüttenhelm BN, Duraku LS, Dijkstra JF, Walbeehm ET, Holstege JC. Differential Changes in the Peptidergic and the Non-Peptidergic Skin Innervation in Rat Models for Inflammation, Dry Skin Itch, and Dermatitis. J Invest Dermatol 2015; 135:2049-2057. [PMID: 25848979 DOI: 10.1038/jid.2015.137] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 11/25/2014] [Accepted: 12/11/2014] [Indexed: 01/07/2023]
Abstract
Skin innervation is a dynamic process that may lead to changes in nerve fiber density during pathological conditions. We have investigated changes in epidermal nerve fiber density in three different rat models that selectively produce chronic itch (the dry skin model), or itch and inflammation (the dermatitis model), or chronic inflammation without itch (the CFA model). In the epidermis, we identified peptidergic fibers-that is, immunoreactive (IR) for calcitonin gene-related peptide or substance P—and non-peptidergic fibers—that is, IR for P2X3. The overall density of nerve fibers was determined using IR for the protein gene product 9.5. In all three models, the density of epidermal peptidergic nerve fibers increased up to five times when compared with a sham-treated control group. In contrast, the density of epidermal non-peptidergic fibers was not increased, except for a small but significant increase in the dry skin model. Chronic inflammation showed an increased density of peptidergic fibers without itch, indicating that increased nerve fiber density is not invariably associated with itch. The finding that different types of skin pathology induced differential changes in nerve fiber density may be used as a diagnostic tool in humans, through skin biopsies, to identify different types of pathology and to monitor the effect of therapies.
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Affiliation(s)
- Barthold N Schüttenhelm
- Department of Neuroscience, Erasmus Medical Centre, Rotterdam, The Netherlands; Department of Plastic, Reconstructive and Hand Surgery, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - Liron S Duraku
- Department of Neuroscience, Erasmus Medical Centre, Rotterdam, The Netherlands; Department of Plastic, Reconstructive and Hand Surgery, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - Jouke F Dijkstra
- Department of Neuroscience, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - Erik T Walbeehm
- Department of Plastic Surgery, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Jan C Holstege
- Department of Neuroscience, Erasmus Medical Centre, Rotterdam, The Netherlands.
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Meng FF, Xu Y, Dan QQ, Wei L, Deng YJ, Liu J, He M, Liu W, Xia QJ, Zhou FH, Wang TH, Wang XY. Intrathecal injection of lentivirus-mediated glial cell line-derived neurotrophic factor RNA interference relieves bone cancer-induced pain in rats. Cancer Sci 2015; 106:430-7. [PMID: 25611164 PMCID: PMC4409887 DOI: 10.1111/cas.12609] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 12/30/2014] [Accepted: 01/11/2015] [Indexed: 12/27/2022] Open
Abstract
Bone cancer pain is a common symptom in cancer patients with bone metastases and the underlying mechanisms are largely unknown. The aim of this study is to explore the endogenous analgesic mechanisms to develop new therapeutic strategies for bone-cancer induced pain (BCIP) as a result of metastases. MRMT-1 tumor cells were injected into bilateral tibia of rats and X-rays showed that the area suffered from bone destruction, accompanied by an increase in osteoclast numbers. In addition, rats with bone cancer showed apparent mechanical and thermal hyperalgesia at day 28 after intratibial MRMT-1 inoculation. However, intrathecal injection of morphine or lentivirus-mediated glial cell line-derived neurotrophic factor RNAi (Lvs-siGDNF) significantly attenuated mechanical and thermal hyperalgesia, as shown by increases in paw withdrawal thresholds and tail-flick latencies, respectively. Furthermore, Lvs-siGDNF interference not only substantially downregulated GDNF protein levels, but also reduced substance P immunoreactivity and downregulated the ratio of pERK/ERK, where its activation is crucial for pain signaling, in the spinal dorsal horn of this model of bone-cancer induced pain. In this study, Lvs-siGDNF gene therapy appeared to be a beneficial method for the treatment of bone cancer pain. As the effect of Lvs-siGDNF to relieve pain was similar to morphine, but it is not a narcotic, the use of GDNF RNA interference may be considered as a new therapeutic strategy for the treatment of bone cancer pain in the future.
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Affiliation(s)
- Fu-Fen Meng
- Department of Anesthesia, Xinjiang Tumor Hospital, Urumqi, China
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Growth and Turning Properties of Adult Glial Cell–Derived Neurotrophic Factor Coreceptor α1 Nonpeptidergic Sensory Neurons. J Neuropathol Exp Neurol 2014; 73:820-36. [DOI: 10.1097/nen.0000000000000101] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
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Wang C, Wang H, Pang J, Li L, Zhang S, Song G, Li N, Cao J, Zhang L. Glial Cell-Derived Neurotrophic Factor Attenuates Neuropathic Pain in a Mouse Model of Chronic Constriction Injury: Possible Involvement of E-cadherin/p120ctn Signaling. J Mol Neurosci 2014; 54:156-63. [DOI: 10.1007/s12031-014-0266-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Accepted: 02/14/2014] [Indexed: 12/22/2022]
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Murase S, Kato K, Taguchi T, Mizumura K. Glial cell line-derived neurotrophic factor sensitized the mechanical response of muscular thin-fibre afferents in rats. Eur J Pain 2013; 18:629-38. [PMID: 24174387 DOI: 10.1002/j.1532-2149.2013.00411.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/01/2013] [Indexed: 11/07/2022]
Abstract
BACKGROUND The role of glial cell line-derived neurotrophic factor (GDNF) in pain and muscular nociceptor activities is not well understood. We examined pain-related behaviour and mechanical response of muscular thin-fibre afferents after intramuscular injection of GDNF in rats. METHODS GDNF and antagonist to transient receptor potential V1 or acid-sensing ion channels were injected into rat gastrocnemius muscle and muscular mechanical hyperalgesia was assessed with a Randall-Selitto analgesiometer. Activities of single C- (conduction velocity < 2.0 m/s) and Aδ-fibres (conduction velocity 2.0-12.0 m/s) were recorded from extensor digitorum longus muscle-nerve preparations in vitro. The changes in the responses to mechanical stimuli before and after GDNF injection were recorded. RESULTS Mechanical hyperalgesia was observed from 1 h to 1 day after GDNF (0.03 μM, 20 μL) injection. The decreased withdrawal threshold was temporarily reversed after intramuscular injection of amiloride (50 mM, 20 μL), but not capsazepine (50 μM, 20 μL). In single-fibre recordings, both phosphate buffered saline (PBS) and GDNF failed to induce any significant discharges. GDNF significantly enhanced the mechanical response when compared with the PBS group, but only in Aδ-fibre afferents. C-fibres were not affected. Significantly lowered threshold and increased response magnitude to mechanical stimuli were observed 30 or 60-120 min after injection. These times are compatible with the timing of the onset of the hyperalgesic effect of GDNF. CONCLUSIONS These results suggest that GDNF increased the response of muscular Aδ-fibre afferents to mechanical stimuli, resulting in muscular mechanical hyperalgesia.
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Affiliation(s)
- S Murase
- Department of Physical Therapy, College of Life and Health Sciences, Chubu University, Kasugai, Japan; Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Japan
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Ota H, Katanosaka K, Murase S, Kashio M, Tominaga M, Mizumura K. TRPV1 and TRPV4 play pivotal roles in delayed onset muscle soreness. PLoS One 2013; 8:e65751. [PMID: 23799042 PMCID: PMC3684597 DOI: 10.1371/journal.pone.0065751] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Accepted: 04/29/2013] [Indexed: 11/18/2022] Open
Abstract
Unaccustomed strenuous exercise that includes lengthening contraction (LC) often causes tenderness and movement related pain after some delay (delayed-onset muscle soreness, DOMS). We previously demonstrated that nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF) are up-regulated in exercised muscle through up-regulation of cyclooxygenase (COX)-2, and they sensitized nociceptors resulting in mechanical hyperalgesia. There is also a study showing that transient receptor potential (TRP) ion channels are involved in DOMS. Here we examined whether and how TRPV1 and/or TRPV4 are involved in DOMS. We firstly evaluated a method to measure the mechanical withdrawal threshold of the deep tissues in wild-type (WT) mice with a modified Randall-Selitto apparatus. WT, TRPV1−/− and TRPV4−/− mice were then subjected to LC. Another group of mice received injection of murine NGF-2.5S or GDNF to the lateral gastrocnemius (LGC) muscle. Before and after these treatments the mechanical withdrawal threshold of LGC was evaluated. The change in expression of NGF, GDNF and COX-2 mRNA in the muscle was examined using real-time RT-PCR. In WT mice, mechanical hyperalgesia was observed 6–24 h after LC and 1–24 h after NGF and GDNF injection. LC induced mechanical hyperalgesia neither in TRPV1−/− nor in TRPV4−/− mice. NGF injection induced mechanical hyperalgesia in WT and TRPV4−/− mice but not in TRPV1−/− mice. GDNF injection induced mechanical hyperalgesia in WT but neither in TRPV1−/− nor in TRPV4−/− mice. Expression of NGF and COX-2 mRNA was significantly increased 3 h after LC in all genotypes. However, GDNF mRNA did not increase in TRPV4−/− mice. These results suggest that TRPV1 contributes to DOMS downstream (possibly at nociceptors) of NGF and GDNF, while TRPV4 is located downstream of GDNF and possibly also in the process of GDNF up-regulation.
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Affiliation(s)
- Hiroki Ota
- Department of Neural Regulation, Graduate School of Medicine, Nagoya University, Nagoya, Japan
- Department of Physical Therapy, College of Life and Health Sciences, Chubu University, Kasugai, Japan
| | - Kimiaki Katanosaka
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Shiori Murase
- Department of Physical Therapy, College of Life and Health Sciences, Chubu University, Kasugai, Japan
| | - Makiko Kashio
- Division of Cell Signaling, Okazaki Institute for Integrative Bioscience, National Institute for Physiological Sciences, Okazaki, Japan
| | - Makoto Tominaga
- Division of Cell Signaling, Okazaki Institute for Integrative Bioscience, National Institute for Physiological Sciences, Okazaki, Japan
| | - Kazue Mizumura
- Department of Physical Therapy, College of Life and Health Sciences, Chubu University, Kasugai, Japan
- * E-mail:
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Takeda M, Takahashi M, Hara N, Matsumoto S. Glial cell line-derived neurotrophic factor modulates the excitability of nociceptive trigeminal ganglion neurons via a paracrine mechanism following inflammation. Brain Behav Immun 2013; 28:100-7. [PMID: 23131757 DOI: 10.1016/j.bbi.2012.10.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Accepted: 10/29/2012] [Indexed: 01/05/2023] Open
Abstract
Previous our report indicated that acute application of glial cell line-derived neurotrophic factor (GDNF) enhances the neuronal excitability of adult rat small-diameter trigeminal ganglion (TRG) neurons, which innervate the facial skin in the absence of neuropathic and inflammatory conditions. This study investigated whether under in vivo conditions, GDNF modulates the excitability of nociceptive Aδ-TRG neurons innervating the facial skin via a paracrine mechanism following inflammation. We used extracellular electrophysiological recording with multibarrel-electrodes in this study. Spontaneous Aδ-TRG neuronal activity was induced in control rats after iontophoretic application of GDNF into the trigeminal ganglia (TRGs). Noxious and non-noxious mechanical stimuli evoked Aδ-TRG neuronal firing rate were significantly increased by iontophoretic application of GDNF. The mean mechanical threshold of nociceptive TRG neurons was significantly decreased by GDNF application. The increased discharge frequency and decreased mechanical threshold induced by GDNF were antagonized by application of the protein tyrosine kinase inhibitor, K252b. The number of Aδ-TRG neurons with spontaneous firings and their firing rates in rats with inflammation induced by Complete Freund's Adjuvant were significantly higher than control rats. The firing rates of Aδ-TRG spontaneous neuronal activity were significantly decreased by iontophoretic application of K252b in inflamed rats. K252b also inhibited Aδ-TRG neuron activity evoked by mechanical stimulation in inflamed rats. These results suggest that in vivo GDNF enhances the excitability of nociceptive Aδ-TRG neurons via a paracrine mechanism within TRGs following inflammation. GDNF paracrine mechanism could be important as a therapeutic target for trigeminal inflammatory hyperalgesia.
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Affiliation(s)
- Mamoru Takeda
- Department of Physiology, School of Life Dentistry at Tokyo, Nippon Dental University, 1-9-20, Fujimi-cho, Chiyoda-ku, Tokyo 102-8159, Japan.
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Spofford CM, Brennan TJ. Gene expression in skin, muscle, and dorsal root ganglion after plantar incision in the rat. Anesthesiology 2012; 117:161-72. [PMID: 22617252 PMCID: PMC3389501 DOI: 10.1097/aln.0b013e31825a2a2b] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
BACKGROUND Treating postoperative pain remains a significant challenge for perioperative medicine. Recent studies have shown that nerve growth factor is up-regulated and contributes to incisional pain. To date, few studies have examined expression of other neurotrophin-related mediators that may contribute to the development and/or maintenance of incisional pain. METHODS Male Sprague-Dawley rats underwent a plantar incision, and pain behaviors were examined (n = 6). In a separate group of rats, expression of neurotrophic factors were studied. At various times after incision (n = 4) or sham surgery (n = 4), the skin, muscle, and dorsal root ganglia were harvested and total RNA isolated. Real-time reverse transcription polymerase chain reaction was performed and the fold change in gene expression was analyzed using significance analysis of microarrays. RESULTS Several genes were changed (P < 0.05) as early as 1 h after incision. Expression of artemin and nerve growth factor were increased in both incised skin and muscle. Brain-derived neurotrophic factor, neurotrophin-3, and neurotrophin-5 were all down-regulated in the skin but up-regulated in the muscle 48 h after incision. Few genes changed in the dorsal root ganglion. Most changes in expression occurred in the first 48 h after incision, a timeframe when pain behavior was the greatest. CONCLUSION Surgical incision is associated with pain-related gene expression changes in skin, muscle, and, to a lesser extent, dorsal root ganglion. The gene expression profile provides clues as to mediators that are involved in peripheral sensitization and pain transmission after surgical incision and also suggest mechanisms for resolution of postoperative pain when more persistent pain syndromes like neuropathic pain continue.
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Hendrich J, Alvarez P, Chen X, Levine JD. GDNF induces mechanical hyperalgesia in muscle by reducing I(BK) in isolectin B4-positive nociceptors. Neuroscience 2012; 219:204-13. [PMID: 22704965 DOI: 10.1016/j.neuroscience.2012.06.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 06/04/2012] [Accepted: 06/06/2012] [Indexed: 10/28/2022]
Abstract
We have assessed the mechanism underlying glial cell-derived neurotrophic factor (GDNF)-induced mechanical hyperalgesia in the gastrocnemius muscle, using patch clamp electrophysiology, in vivo electrophysiology and behavioral studies. Cultured isolectin B4-positive (IB4+) dorsal root ganglion neurons that innervated this muscle were held under current clamp; the majority developed an increase in action potential duration (a factor of increase of 2.29±0.24, compared to 1.13±0.17 in control, P<0.01) in response to GDNF (200 ng/ml) by 15 min after application. They also demonstrated a depolarization of resting membrane potential, but without significant changes in rheobase, action potential peak, or after-hyperpolarization. Large-conductance voltage- and calcium-activated potassium (BK) channels, which have recently been shown to play a role in the repolarization of IB4+ nociceptors, were inhibited under voltage clamp, as indicated by a significant reduction in the iberiotoxin-sensitive current. In vivo single-fiber recording from muscle afferents revealed that injection of iberiotoxin into their peripheral nociceptive field caused an increase in nociceptor firing in response to a 60s suprathreshold stimulus (an increase from 392.2±119.8 spikes to 596.1±170.8 spikes, P<0.05). This was observed in the absence of changes in the mechanical threshold. Finally, injection of iberiotoxin into the gastrocnemius muscle produced dose-dependent mechanical hyperalgesia. These data support the suggestion that GDNF induces nociceptor sensitization and mechanical hyperalgesia, at least in part, by inhibiting BK current in IB4+ nociceptors.
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Affiliation(s)
- J Hendrich
- Department of Oral and Maxillofacial Surgery, University of California at San Francisco, CA 94143-0440, USA
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Guo J, Jia D, Jin B, Xu F, Yuan X, Shen H. Effects of Glial Cell Line-Derived Neurotrophic Factor Intrathecal Injection on Spinal Dorsal Horn Glial Fibrillary Acidic Protein Expression in a Rat Model of Neuropathic Pain. Int J Neurosci 2012; 122:388-94. [DOI: 10.3109/00207454.2012.672500] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Takasu K, Sakai A, Hanawa H, Shimada T, Suzuki H. Overexpression of GDNF in the uninjured DRG exerts analgesic effects on neuropathic pain following segmental spinal nerve ligation in mice. THE JOURNAL OF PAIN 2012; 12:1130-9. [PMID: 21684216 DOI: 10.1016/j.jpain.2011.04.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 02/28/2011] [Accepted: 04/04/2011] [Indexed: 02/05/2023]
Abstract
UNLABELLED Glial cell line-derived neurotrophic factor (GDNF), a survival-promoting factor for a subset of nociceptive small-diameter neurons, has been shown to exert analgesic effects on neuropathic pain. However, its detailed mechanisms of action are still unknown. In the present study, we investigated the site-specific analgesic effects of GDNF in the neuropathic pain state using lentiviral vector-mediated GDNF overexpression in mice with left fifth lumbar (L5) spinal nerve ligation (SNL) as a neuropathic pain model. A lentiviral vector expressing both GDNF and enhanced green fluorescent protein (EGFP) was constructed and injected into the left dorsal spinal cord, uninjured fourth lumbar (L4) dorsal root ganglion (DRG), injured L5 DRG, or plantar skin of mice. In SNL mice, injection of the GDNF-EGFP-expressing lentivirus into the dorsal spinal cord or uninjured L4 DRG partially but significantly reduced the mechanical allodynia in association with an increase in GDNF protein expression in each virus injection site, whereas injection into the injured L5 DRG or plantar skin had no effects. These results suggest that GDNF exerts its analgesic effects in the neuropathic pain state by acting on the central terminals of uninjured DRG neurons and/or on the spinal cells targeted by the uninjured DRG neurons. PERSPECTIVE This article shows that GDNF exerts its analgesic effects on neuropathic pain by acting on the central terminals of uninjured DRG neurons and/or on the spinal cells targeted by these neurons. Therefore, research focusing on these GDNF-dependent neurons in the uninjured DRG would provide a new strategy for treating neuropathic pain.
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Affiliation(s)
- Kumiko Takasu
- Department of Pharmacology, Nippon Medical School, Tokyo, Japan
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Intervertebral Disc Degeneration-induced Expression of Pain-related Molecules. J Neurosurg Anesthesiol 2011; 23:329-34. [DOI: 10.1097/ana.0b013e318220f033] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Andres C, Meyer S, Dina OA, Levine JD, Hucho T. Quantitative automated microscopy (QuAM) elucidates growth factor specific signalling in pain sensitization. Mol Pain 2010; 6:98. [PMID: 21187008 PMCID: PMC3023724 DOI: 10.1186/1744-8069-6-98] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Accepted: 12/27/2010] [Indexed: 01/19/2023] Open
Abstract
Background Dorsal root ganglia (DRG)-neurons are commonly characterized immunocytochemically. Cells are mostly grouped by the experimenter's eye as "marker-positive" and "marker-negative" according to their immunofluorescence intensity. Classification criteria remain largely undefined. Overcoming this shortfall, we established a quantitative automated microscopy (QuAM) for a defined and multiparametric analysis of adherent heterogeneous primary neurons on a single cell base. The growth factors NGF, GDNF and EGF activate the MAP-kinase Erk1/2 via receptor tyrosine kinase signalling. NGF and GDNF are established factors in regeneration and sensitization of nociceptive neurons. If also the tissue regenerating growth factor, EGF, influences nociceptors is so far unknown. We asked, if EGF can act on nociceptors, and if QuAM can elucidate differences between NGF, GDNF and EGF induced Erk1/2 activation kinetics. Finally, we evaluated, if the investigation of one signalling component allows prediction of the behavioral response to a reagent not tested on nociceptors such as EGF. Results We established a software-based neuron identification, described quantitatively DRG-neuron heterogeneity and correlated measured sample sizes and corresponding assay sensitivity. Analysing more than 70,000 individual neurons we defined neuronal subgroups based on differential Erk1/2 activation status in sensory neurons. Baseline activity levels varied strongly already in untreated neurons. NGF and GDNF subgroup responsiveness correlated with their subgroup specificity on IB4(+)- and IB4(-)-neurons, respectively. We confirmed expression of EGF-receptors in all sensory neurons. EGF treatment induced STAT3 translocation into the nucleus. Nevertheless, we could not detect any EGF induced Erk1/2 phosphorylation. Accordingly, intradermal injection of EGF resulted in a fundamentally different outcome than NGF/GDNF. EGF did not induce mechanical hyperalgesia, but blocked PGE2-induced sensitization. Conclusions QuAM is a suitable if not necessary tool to analyze activation of endogenous signalling in heterogeneous cultures. NGF, GDNF and EGF stimulation of DRG-neurons shows differential Erk1/2 activation responses and a corresponding differential behavioral phenotype. Thus, in addition to expression-markers also signalling-activity can be taken for functional subgroup differentiation and as predictor of behavioral outcome. The anti-nociceptive function of EGF is an intriguing result in the context of tissue damage but also for understanding pain resulting from EGF-receptor block during cancer therapy.
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Affiliation(s)
- Christine Andres
- Department for Molecular Human Genetics, Max Planck Institute for Molecular Genetics, Ihnestrasse 73, Berlin, Germany
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Vivoli E, Di Cesare Mannelli L, Salvicchi A, Bartolini A, Koverech A, Nicolai R, Benatti P, Ghelardini C. Acetyl-L-carnitine increases artemin level and prevents neurotrophic factor alterations during neuropathy. Neuroscience 2010; 167:1168-74. [PMID: 20302919 DOI: 10.1016/j.neuroscience.2010.03.017] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2010] [Revised: 03/08/2010] [Accepted: 03/08/2010] [Indexed: 12/25/2022]
Abstract
Damages to the nervous system are the primarily cause of neuropathy and chronic pain. Current pharmacological treatments for neuropathic pain are not able to prevent or revert morphological and molecular consequences of tissue injury. On the other hand, many neurotrophins, like nerve growth factor (NGF), paired off restorative effects with hyperalgesia. Interestingly, the glial cell line-derived neurotrophic factors GDNF and Artemin (ARTN) seem to support neuron survival and to normalize abnormal pain behaviour. In the present research protein levels of NGF, GDNF and ARTN were evaluated in a rat model of peripheral neuropathy, the chronic constriction injury (CCI). NGF was increased by CCI in the ipsilateral dorsal root ganglia (DRG), in the spinal cord and in the periaqueductal grey matter (PAG). On the contrary, ARTN was decreased bilaterally in DRG, spinal cord and PAG. GDNF levels decreased in ipsilateral DRG, whereas the constriction did not modify its expression in the central nervous system districts. Repeated treatments with the antihyperalgesic and neuroregenerative compound acetyl-l-carnitine (ALCAR; 100 mgkg(-1) i.p. twice daily for 15 days) was able to prevent the increase of NGF levels. In conditions of pain relief ALCAR normalized peripheral and central alterations of GDNF and ARTN levels. Characteristically, sham animals that underwent the same ALCAR treatment, showed increased levels of ARTN both in the DRG and in the spinal cord. These data offer a new point of view on the mechanism of the antihyperalgesic as well as the neuroprotective effect of ALCAR.
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Affiliation(s)
- E Vivoli
- Department of Preclinical and Clinical Pharmacology, University of Florence, Viale Pieraccini 6, 50139, Florence, Italy
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Lundborg C, Hahn-Zoric M, Biber B, Hansson E. Glial cell line-derived neurotrophic factor is increased in cerebrospinal fluid but decreased in blood during long-term pain. J Neuroimmunol 2010; 220:108-13. [PMID: 20129677 DOI: 10.1016/j.jneuroim.2010.01.007] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Revised: 01/12/2010] [Accepted: 01/13/2010] [Indexed: 01/14/2023]
Abstract
Glial cell line-derived neurotrophic factor (GDNF) is involved in inflammation and pain, roles which remain to be delineated clinically. We aimed to evaluate the role of central nervous and peripheral GDNF in long-term pain patients and in controls by analysing intrathecal and blood concentrations of GDNF. Simultaneous measurements of pro-inflammatory cytokines IL-1beta, TNF-alpha and IL-6, anti-inflammatory cytokine IL-10 and chemokine IL-8 served to define inflammatory responses. Generally, blood levels of GDNF were higher than corresponding intrathecal levels. Pain was associated with levels of GDNF that were increased intrathecally, but decreased in blood. IL-8 was uniformly higher in pain patients.
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Affiliation(s)
- Christopher Lundborg
- Department of Anaesthesiology and Intensive Care Medicine, Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, 413 45 Gothenburg, Sweden.
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Takeda M, Kitagawa J, Nasu M, Takahashi M, Iwata K, Matsumoto S. Glial cell line-derived neurotrophic factor acutely modulates the excitability of rat small-diameter trigeminal ganglion neurons innervating facial skin. Brain Behav Immun 2010; 24:72-82. [PMID: 19679180 DOI: 10.1016/j.bbi.2009.08.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2009] [Revised: 07/14/2009] [Accepted: 08/05/2009] [Indexed: 12/31/2022] Open
Abstract
Glial cell line-derived neurotrophic factor (GDNF) plays an important role in adult sensory neuron function. However, the acute effects of GDNF on primary sensory neuron excitability remain to be elucidated. The aim of the present study was to investigate whether GDNF acutely modulates the excitability of adult rat trigeminal ganglion (TRG) neurons that innervate the facial skin by using perforated-patch clamping, retrograde-labeling and immunohistochemistry techniques. Fluorogold (FG) retrograde labeling was used to identify the TRG neurons innervating the facial skin. The FG-labeled small- and medium-diameter GDNF immunoreactive TRG neurons, and most of these neurons also expressed the GDNF family receptor alpha-1 (GFRalpha-1). In whole-cell voltage-clamp mode, GDNF application significantly inhibited voltage-gated K(+) transient (I(A)) and sustained (I(K)) currents in most dissociated FG-labeled small-diameter TRG neurons. This effect was concentration-dependent and was abolished by co-application of the protein tyrosine kinase inhibitor, K252b. Under current-clamp conditions, the repetitive firing during a depolarizing pulse were significantly increased by GDNF application. GDNF application also increased the duration of the repolarization phase and decreased the duration of the depolarization phase of the action potential, and these characteristic effects were also abolished by co-application of K252b. These results suggest that acute application of GDNF enhances the neuronal excitability of adult rat small-diameter TRG neurons innervating the facial skin, via activation of GDNF-induced intracellular signaling pathway. We therefore conclude that a local release of GDNF from TRG neuronal soma and/or nerve terminals may regulate normal sensory function, including nociception.
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Affiliation(s)
- Mamoru Takeda
- Department of Physiology, School of Life Dentistry at Tokyo, Nippon Dental University, 1-9-20, Fujimi-cho, Chiyoda-ku, Tokyo 102-8159, Japan.
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Acute and chronic effects of neurotrophic factors BDNF and GDNF on responses mediated by thermo-sensitive TRP channels in cultured rat dorsal root ganglion neurons. Brain Res 2009; 1284:54-67. [DOI: 10.1016/j.brainres.2009.06.014] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2009] [Revised: 06/05/2009] [Accepted: 06/06/2009] [Indexed: 11/22/2022]
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Spinal cord long-term potentiation (LTP) is associated with increased dorsal horn gene expression of IL-1beta, GDNF and iNOS. Eur J Pain 2009; 14:255-60. [PMID: 19596210 DOI: 10.1016/j.ejpain.2009.05.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2009] [Revised: 04/24/2009] [Accepted: 05/26/2009] [Indexed: 12/20/2022]
Abstract
Previous data show that spinal cord long-term potentiation (LTP) can be induced by electrical high-frequency stimulation (HFS) conditioning applied to the sciatic nerve. It has been suggested that the cellular events leading to this form of plasticity may contribute to central hyperalgesia. In the present study, extracellular recordings from single dorsal horn neurons and quantitative real-time reverse-transcriptase polymerase chain reaction (RT-PCR) on rat dorsal horn tissue were used to examine whether maintenance of spinal LTP is associated with changes in gene expression of the proinflammatory interleukin-1beta (IL-1beta), glial cell-line derived neurotrophic factor (GDNF), inducible nitric oxide synthase (iNOS), p38 mitogen-activated protein kinase (p38 MAPK), cyclooxygenase 2 (COX2) and tumor necrosis factor alpha (TNFalpha). The data demonstrated that the HFS conditioning induced a robust increase in the dorsal horn C-fibre responses, which outlasted the duration of the experiments of 6h (p<0.05, HFS vs. control). Moreover, a significant increase in the expression of mRNA for IL-1beta, GDNF and iNOS were observed 6h following the HFS conditioning (p<0.05, HFS vs. control). For the first time we show that spinal cord LTP is associated with an increased dorsal horn expression of the genes for IL-1beta, GDNF and iNOS.
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Russell FA, Fernandes ES, Courade JP, Keeble JE, Brain SD. Tumour necrosis factor alpha mediates transient receptor potential vanilloid 1-dependent bilateral thermal hyperalgesia with distinct peripheral roles of interleukin-1beta, protein kinase C and cyclooxygenase-2 signalling. Pain 2009; 142:264-274. [PMID: 19231080 DOI: 10.1016/j.pain.2009.01.021] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Revised: 01/15/2009] [Accepted: 01/21/2009] [Indexed: 11/21/2022]
Abstract
TNFalpha plays a pivotal role in rheumatoid arthritis (RA) but little is known of the mechanisms that link the inflammatory and nociceptive effects of TNFalpha. We have established a murine model of TNFalpha-induced TRPV1-dependent bilateral thermal hyperalgesia that then allowed us to identify distinct peripheral mechanisms involved in mediating TNFalpha-induced ipsilateral and contralateral hyperalgesia. Thermal hyperalgesia and inflammation were assessed in both hindpaws following unilateral intraplantar (i.pl.) TNFalpha. The hyperalgesic mechanisms were analysed through pharmacogenetic approaches involving TRPV1(-/-) mice and TRPV1 antagonists. To study the mediators downstream of TNFalpha, cyclooxygenase (COX) and PKC inhibitors were utilised and cytokine and prostaglandin levels assessed. The role of neutrophils was determined through use of the selectin inhibitor, fucoidan. We show that TNFalpha (10pmol) causes thermal hyperalgesia (1-4h) in the ipsilateral inflamed and contralateral uninjured hindpaws, which is TRPV1-dependent. GF109203X, a PKC inhibitor, suppressed the hyperalgesia indicating that PKC is involved in TRPV1 sensitisation. Ipsilateral COX-2-derived prostaglandins were also crucial to the development of the bilateral hyperalgesia. The prevention of neutrophil accumulation with fucoidan attenuated hyperalgesia at 4 but not at 1h, indicating a role in the maintenance but not in the induction of bilateral hyperalgesia. However, TNFalpha-induced IL-1beta generation in both paws and the presence of local IL-1beta in the contralateral paw were essential for the development of bilateral hyperalgesia. These results identify a series of peripheral events through which TNFalpha triggers and maintains bilateral inflammatory pain. This potentially allows a better understanding of mechanisms involved in TNFalpha-dependent pain pathways in symmetrical diseases such as arthritis.
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Affiliation(s)
- Fiona A Russell
- Cardiovascular Division, Franklin-Wilkins Building, King's College London, Waterloo Campus, 150 Stamford St., London SE1 9NH, UK IPC 351, Pain Therapeutic Area, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, UK
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33
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Sakai A, Asada M, Seno N, Suzuki H. Involvement of neural cell adhesion molecule signaling in glial cell line-derived neurotrophic factor-induced analgesia in a rat model of neuropathic pain. Pain 2008; 137:378-388. [PMID: 17967506 DOI: 10.1016/j.pain.2007.09.020] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2006] [Revised: 08/20/2007] [Accepted: 09/24/2007] [Indexed: 11/16/2022]
Abstract
Since neuropathic pain is resistant to conventional analgesics such as opiates and non-steroidal anti-inflammatory drugs, the development of new types of drugs for its treatment has been awaited. Several key molecules associated with nociception have been suggested as potential targets for new analgesics. Glial cell line-derived neurotrophic factor (GDNF) has a variety of functions affecting the survival and development of specified neural cell populations, mediated via transmission of intracellular signals through binding to its high-affinity receptor, GFR*1, and subsequent activation of a tyrosine receptor kinase, RET, neural cell adhesion molecule (NCAM), or other signaling molecules. GDNF also exhibits analgesic effects in rodent models of neuropathic pain, although the underlying mechanisms are still largely unknown, including the intracellular signal transduction involved. We report here that NCAM signaling plays a role in mediating the analgesic effect of GDNF in rats with chronic constrictive injury (CCI). We found that NCAM was expressed in intrinsic neurons in the spinal dorsal horn and in dorsal root ganglion neurons with small cell bodies. Reduction of NCAM expression by NCAM antisense oligodeoxynucleotide administration to CCI rats abolished the analgesic effect of GDNF without affecting RET signaling activation. An NCAM mimetic peptide, C3d, partially reduced the chronic pain induced by CCI. These findings suggest that NCAM signaling plays a critical role in the analgesic effect of GDNF and that development of new drugs activating GDNF-NCAM signaling may represent a new strategy for the relief of intractable pain.
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Affiliation(s)
- Atsushi Sakai
- Department of Pharmacology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8602, Japan Pharmaceutical Research Center, Kyowa Hakko Kogyo Co., Shizuoka 411-8731, Japan
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Quintão NLM, Santos ARS, Campos MM, Calixto JB. The role of neurotrophic factors in genesis and maintenance of mechanical hypernociception after brachial plexus avulsion in mice. Pain 2007; 136:125-33. [PMID: 17706869 DOI: 10.1016/j.pain.2007.06.027] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2006] [Revised: 06/14/2007] [Accepted: 06/20/2007] [Indexed: 01/03/2023]
Abstract
Neurotrophic factors (NTFs), namely nerve growth factor (NGF), glial cell line-derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3), have recently emerged as a new exciting class of potential targets for the development of drugs to treat chronic pain. We have recently reported that brachial plexus avulsion (BPA) results in a marked and long-lasting mechanical hypernociception in rodents. Here we demonstrate that antibodies against NGF, NT-3, GDNF and BDNF were able to postpone the mechanical hypernociception in mice when dosed locally, systemically or intrathecally (i.t.) at the time of surgery. However, none of them were able to interfere with the mechanical hypernociception when administered intraventricularly (i.c.v.) at the moment of surgery or even i.p. on the 4th day after the injury. Interestingly, the anti-BDNF antibody was the only one that substantially reversed the mechanical hypernociceptive state when administered i.t. or i.c.v. on the 4th day after the BPA. We might suggest that NTFs, notably BDNF, are involved in the mechanisms underlying neuropathic pain-like behavior following BPA. These pieces of evidence corroborate the notion that NTF blockers might represent a new and interesting option for the management of neuropathic pain.
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Affiliation(s)
- Nara Lins Meira Quintão
- Department of Pharmacology, Centre of Biological Sciences, Universidade Federal de Santa Catarina, 88049-900 Florianópolis, SC, Brazil
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Jongen JLM, Jaarsma D, Hossaini M, Natarajan D, Haasdijk ED, Holstege JC. Distribution of RET immunoreactivity in the rodent spinal cord and changes after nerve injury. J Comp Neurol 2007; 500:1136-53. [PMID: 17183535 DOI: 10.1002/cne.21234] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
RET (for "rearranged during transfection") is a transmembrane tyrosine kinase signaling receptor for members of the glial cell line-derived neurotrophic factor (GDNF) family of ligands. We used RET immunohistochemistry (IHC), double-labeling immunofluorescence (IF), and in situ hybridization (ISH) in adult naïve and nerve-injured rats to study the distribution of RET in the spinal cord. In the dorsal horn, strong RET-immunoreactive (-ir) fibers were abundant in lamina II-inner (II(i)), although this labeling was preferentially observed after an antigen-unmasking procedure. After dorsal rhizotomy, RET-ir fibers in lamina II(i) completely disappeared from the dorsal horn, indicating that they were all primary afferents. After peripheral axotomy, RET-ir in primary afferents decreased in lamina II(i) and appeared to increase slightly in laminae III and IV. RET-ir was also observed in neurons and dendrites throughout the dorsal horn. Some RET-ir neurons in lamina I had the morphological appearance of nociceptive projection neurons, which was confirmed by the finding that 53% of RET-ir neurons in lamina I colocalized with neurokinin-1. GDNF-ir terminals were in close proximity to RET-ir neurons in the superficial dorsal horn. In the ventral horn, RET-ir was strongly expressed by motoneurons, with the strongest staining in small, presumably gamma-motoneurons. Increased RET expression following peripheral axotomy was most pronounced in alpha-motoneurons. The expression and regulation pattern of RET in the spinal cord are in line with its involvement in regenerative processes following nerve injury. The presence of RET in dorsal horn neurons, including nociceptive projection neurons, suggests that RET also has a role in signal transduction at the spinal level. This role may include mediating the effects of GDNF released from nociceptive afferent fibers.
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Affiliation(s)
- Joost L M Jongen
- Department of Neuroscience, Erasmus MC-University Medical Center Rotterdam, 3015 GE Rotterdam, The Netherlands.
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Yang H, Bernanke JM, Naftel JP. Immunocytochemical evidence that most sensory neurons of the rat molar pulp express receptors for both glial cell line-derived neurotrophic factor and nerve growth factor. Arch Oral Biol 2006; 51:69-78. [PMID: 16444814 DOI: 10.1016/j.archoralbio.2005.05.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Most pulpal afferent neurons have cytochemical features in common with the class of nociceptors that express neuropeptides and respond to NGF, while very few bind the plant lectin IB4, a widely used marker for the class of nociceptors that respond to the GDNF family of neurotrophic factors. The present study was undertaken to determine whether the GDNF receptor, GFRalpha-1, is expressed by pulpal afferents, and, further, to determine whether tooth injury evokes changes in expression of the GDNF and NGF receptors among pulpal afferents. The tracer, fluoro-gold (FG), was applied to shallow cavities in dentin of first and second maxillary molars. After 4 weeks, the molars of one side received a test injury consisting of a deeper cavity that exposed pulp horns. Animals were perfusion fixed 2 days later, and sections of the trigeminal ganglia were double immunostained with combinations of antibodies against GFRalpha-1, and TrkA. Under control conditions, GFRalpha-1 immunostaining was observed in 72% of neurons that projected to the molar pulp, TrkA in 78%, and immunostaining for both receptors was observed in 65% of pulpal afferents. Tooth injury evoked up-regulation of GFRalpha-1 expression (to 93%) and a slight down-regulation of TrkA expression (67%) among tooth afferents, while there was no discernable change in the proportion of pulpal afferents that expressed both TrkA and GFRalpha-1 (to 61%).
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Affiliation(s)
- Hong Yang
- Department of Anatomy, University of Mississippi Medical Center, Jackson, 39216, USA
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37
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Albers KM, Woodbury CJ, Ritter AM, Davis BM, Koerber HR. Glial cell-line-derived neurotrophic factor expression in skin alters the mechanical sensitivity of cutaneous nociceptors. J Neurosci 2006; 26:2981-90. [PMID: 16540576 PMCID: PMC6673969 DOI: 10.1523/jneurosci.4863-05.2006] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Neurons classified as nociceptors are dependent on nerve growth factor (NGF) during embryonic development, but a large subpopulation lose this dependence during embryonic and postnatal times and become responsive to the transforming growth factor beta family member, glial cell line-derived growth factor (GDNF). To elucidate the functional properties of GDNF-dependent nociceptors and distinguish them from nociceptors that retain NGF dependence, the cellular and physiologic properties of sensory neurons of wild-type and transgenic mice that overexpress GDNF in the skin (GDNF-OE) were analyzed using a skin, nerve, dorsal root ganglion, and spinal cord preparation, immunolabeling, and reverse transcriptase-PCR assays. Although an increase in peripheral conduction velocity of C-fibers in GDNF-OE mice was measured, other electrophysiological properties, including resting membrane potential and somal action potentials, were unchanged. We also show that isolectin B4 (IB4)-positive neurons, many of which are responsive to GDNF, exhibited significantly lower thresholds to mechanical stimulation relative to wild-type neurons. However, no change was observed in heat thresholds for the same population of cells. The increase in mechanical sensitivity was found to correlate with significant increases in acid-sensing ion channels 2A and 2B and transient receptor potential channel A1, which are thought to contribute to detection of mechanical stimuli. These data indicate that enhanced expression of GDNF in the skin can change mechanical sensitivity of IB4-positive nociceptive afferents and that this may occur through enhanced expression of specific types of channel proteins.
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MESH Headings
- Acid Sensing Ion Channels
- Action Potentials
- Animals
- Calcium Channels/biosynthesis
- Calcium Channels/genetics
- Epidermis/innervation
- Female
- Ganglia, Spinal/physiology
- Gene Expression Regulation
- Genes, Synthetic
- Glial Cell Line-Derived Neurotrophic Factor/biosynthesis
- Glial Cell Line-Derived Neurotrophic Factor/genetics
- Glial Cell Line-Derived Neurotrophic Factor/physiology
- Hot Temperature
- Keratin-14
- Keratins/genetics
- Male
- Membrane Proteins/biosynthesis
- Membrane Proteins/genetics
- Mice
- Mice, Inbred C3H
- Mice, Transgenic
- Nerve Fibers, Unmyelinated/physiology
- Nerve Fibers, Unmyelinated/ultrastructure
- Nerve Tissue Proteins/biosynthesis
- Nerve Tissue Proteins/genetics
- Neurons, Afferent/metabolism
- Neurons, Afferent/physiology
- Neurons, Afferent/ultrastructure
- Nociceptors/physiology
- Pain Threshold/physiology
- Physical Stimulation
- Promoter Regions, Genetic
- Sodium Channels/biosynthesis
- Sodium Channels/genetics
- Stress, Mechanical
- TRPV Cation Channels/biosynthesis
- TRPV Cation Channels/genetics
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Keeble J, Russell F, Curtis B, Starr A, Pinter E, Brain SD. Involvement of transient receptor potential vanilloid 1 in the vascular and hyperalgesic components of joint inflammation. ACTA ACUST UNITED AC 2005; 52:3248-56. [PMID: 16200599 DOI: 10.1002/art.21297] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE To investigate the endogenous involvement of transient receptor potential vanilloid 1 (TRPV1) in a model of knee joint inflammation in the mouse. METHODS Following characterization of wild-type (WT) and TRPV1-knockout mice, inflammation was induced via intraarticular (IA) injection of Freund's complete adjuvant (CFA). Knee swelling was assessed as diameter, and inflammatory heat hyperalgesia was determined using the Hargreaves technique, for up to 3 weeks. At 18 hours, acute hyperpermeability was measured with 125I-albumin, and cytokines and myeloperoxidase activity, a marker of neutrophils, were assayed in synovial fluid extracts. The possibility that exogenous tumor necrosis factor alpha (TNFalpha) was involved in influencing TRPV1 activation was investigated in separate experiments. RESULTS Increased levels of knee swelling, hyperpermeability, leukocyte accumulation, and TNFalpha were found in WT mice 18 hours after IA CFA treatment compared with saline treatment. Significantly less knee swelling and hyperpermeability were found in TRPV1-/- mice, but leukocyte accumulation and TNFalpha levels were similar in WT and TRPV1-/- mice. Knee swelling in response to CFA remained significantly higher for a longer period in WT mice compared with TRPV1-/- mice, with thermal hyperalgesic sensitivity observed at 24 hours and at 1 week in WT, but not TRPV1-/-, mice. Knee swelling was attenuated (P < 0.05) in TRPV1-/- compared with WT mice 4 hours after IA administration of TNFalpha. CONCLUSION Our findings indicate that TRPV1 has a role in acute and chronic inflammation in the mouse knee joint. Thus, selective antagonism of TRPV1 should be considered as a potential target for treatment of acute and chronic joint inflammation.
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Affiliation(s)
- Julie Keeble
- Cardiovascular Division, New Hunt's House, King's College London, Guy's Campus, London, UK
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39
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Ambalavanar R, Moritani M, Dessem D. Trigeminal P2X3 receptor expression differs from dorsal root ganglion and is modulated by deep tissue inflammation. Pain 2005; 117:280-291. [PMID: 16153775 DOI: 10.1016/j.pain.2005.06.029] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2005] [Revised: 06/03/2005] [Accepted: 06/13/2005] [Indexed: 02/03/2023]
Abstract
The distribution and modulation of the P2X(3) receptor was studied in trigeminal ganglion neurons to provide insight into the role of ATP in craniofacial sensory mechanisms. Binding to the d-galactose specific lectin IB4 was found in 73% of P2X(3)-positive neurons while only 16% of IB4 neurons expressed P2X(3). Neurons expressing P2X(3) alone were significantly larger than IB4-or IB4/P2X(3)-positive neurons. Investigation of target-specificity revealed that 22% of trigeminal ganglion muscle afferent neurons were positive for P2X(3) versus 16% of cutaneous afferent neurons. Muscle P2X(3) afferents were significantly smaller than the overall muscle afferent population while P2X(3) cutaneous afferent neurons were not. Presumptive heteromeric (P2X(2/3)) muscle afferent neurons were also identified and comprised 77% of the P2X(3) muscle afferent population. Muscle afferent neurons co-expressed P2X(3) with either calcitonin gene-related peptide (15%) or substance P (4%). The number of P2X(3)-positive muscle afferent neurons significantly increased one and four days following complete Freund's adjuvant-induced masseter muscle inflammation, but significantly decreased after 12 days. These results indicate that within trigeminal ganglia: (1) the P2X(3) receptor is expressed in both small and medium-sized neurons; (2) the P2X(3) receptor is not exclusively expressed in IB4 neurons; (3) P2X(3) is co-expressed with neuropeptides; (4) differences in the proportion of cutaneous versus muscle P2X(3) afferents are not apparent. Trigeminal P2X(3) neurons therefore differ markedly from dorsal root ganglion P2X(3) afferents. This study also shows that deep tissue inflammation modulates expression of the P2X(3) receptor and thus may warrant exploration as a target for therapeutic intervention.
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Affiliation(s)
- Ranjinidevi Ambalavanar
- Department of Biomedical Sciences and Program in Neuroscience, University of Maryland, 666 West Baltimore Street, Baltimore, MD 21201, USA Department of Oral Anatomy and Neurobiology, Osaka University, Osaka 565-0871, Japan
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40
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Jongen JLM, Haasdijk ED, Sabel-Goedknegt H, van der Burg J, Vecht CJ, Holstege JC. Intrathecal injection of GDNF and BDNF induces immediate early gene expression in rat spinal dorsal horn. Exp Neurol 2005; 194:255-66. [PMID: 15899262 DOI: 10.1016/j.expneurol.2005.02.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2004] [Revised: 02/07/2005] [Accepted: 02/07/2005] [Indexed: 01/24/2023]
Abstract
Glial cell line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF) are potent trophic factors for dorsal root ganglion cells. In addition, these factors are produced in subsets of dorsal root ganglion cells and transported anterogradely to their terminals in the superficial dorsal horn of the spinal cord, where they constitute the only source of GDNF and BDNF. We investigated the effect of 10 mug GDNF and BDNF injected by lumbar puncture on the expression of the immediate early gene (IEG) products c-Fos, c-Jun, and Krox-24 in the adult rat dorsal horn. In the dorsal horn of S1 spinal segments, GDNF and BDNF induced a strong increase in IEG expression, which was most pronounced in laminae I and II (2.9- to 4.5-fold). More distal from the injection site, in the dorsal horn of L1/L2 spinal segments, the increase in IEG expression was less pronounced, suggesting a concentration-dependent effect. In order to explain the effects of intrathecally injected GDNF, we investigated whether lumbo-sacral dorsal horn neurons expressed RET protein, the signal-transducing element of the receptor complex for GDNF. It was found that several of these neurons contained RET immunoreactivity and that some of the RET-labeled neurons had the appearance of nociceptive-specific cells, confirming their presumed role in pain transmission. Additionally, using double-labeling immunofluorescence combined with confocal microscopy, it was found that after intrathecal GDNF injection 35% of c-Fos-labeled cells were also labeled for RET. These results demonstrate that intrathecally administered GDNF and BDNF induce IEG expression in dorsal horn neurons in the adult rat, supposedly by way of their cognate receptors, which are present on these neurons. We further suggest that the endogenous release of GDNF and BDNF, triggered by nociceptive stimuli, is involved in the induction of changes in spinal nociceptive transmission as in various pain states.
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Affiliation(s)
- J L M Jongen
- Department of Neuroscience, Erasmus MC-University Medical Center Rotterdam, Dr. Molewaterplein 50, 3015 GE, Rotterdam, The Netherlands.
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Tamura S, Morikawa Y, Senba E. TRPV2, a capsaicin receptor homologue, is expressed predominantly in the neurotrophin-3-dependent subpopulation of primary sensory neurons. Neuroscience 2005; 130:223-8. [PMID: 15561438 DOI: 10.1016/j.neuroscience.2004.09.021] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/04/2004] [Indexed: 11/26/2022]
Abstract
TRPV2, a member of transient receptor potential ion channels, responds to high-threshold noxious heat, but neither to capsaicin nor to proton. Although TRPV2 is expressed in medium- to large-sized dorsal root ganglion (DRG) neurons with myelinated fibers in adult rodents, little is known about the neurotrophin dependence of TRPV2-positive neurons in the developing and adult DRGs of mice. In the present study, using immunohistochemistry, we found that TRPV2 was first expressed in DRG neurons at embryonic day (E) 11.5, when neither TRPV1 nor TRPM8 was detected yet. Double-immunofluorescence staining revealed that tyrosine kinase receptor C (TrkC) was expressed in most of TRPV2-positive DRG neurons at E11.5 and E13.5. In addition, the percentage of TRPV2-positive neurons in the total DRG neurons at E13.5 reached the same as that of adulthood. In adult DRGs, TrkC and Ret were expressed in 68% and 25% of TRPV2-positive neurons, respectively. These results suggest that TRPV2 is expressed predominantly in the NT-3-dependent subpopulation of DRG neurons throughout development and in adult mice.
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Affiliation(s)
- S Tamura
- Department of Anatomy and Neurobiology, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509 Japan
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42
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Amaya F, Shimosato G, Nagano M, Ueda M, Hashimoto S, Tanaka Y, Suzuki H, Tanaka M. NGF and GDNF differentially regulate TRPV1 expression that contributes to development of inflammatory thermal hyperalgesia. Eur J Neurosci 2005; 20:2303-10. [PMID: 15525272 DOI: 10.1111/j.1460-9568.2004.03701.x] [Citation(s) in RCA: 186] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The transient receptor potential ion channel, TRPV1 plays an essential role in the development of inflammatory thermal hyperalgesia. We investigated the dependence of inflammatory TRPV1 induction on neurotrophic factor. Rat dorsal root ganglia (DRG) neurons were classified according to immunostaining for trk-A and IB4 and the effects of antibodies against NGF or GDNF on TRPV1 expression within the groups were then analysed by immunohistochemical means. The data were compared with the time course of trophic factor expression and the effects of their antibodies on thermal hyperalgesia against radiant heat after inflammation. Although the levels of both NGF and GDNF were increased by inflammation, NGF rapidly and transiently increased whereas GDNF increased gradually over a period of approximately one week. TRPV1 expression was increased within both trk-A positive and IB4 positive neurons after inflammation. Increased TRPV1 expression within trk-A positive neurons was prevented by anti-NGF but not by anti-GDNF, whereas TRPV1 induction within the IB4 positive group was blocked by anti-GDNF but not by anti-NGF. Both antibodies prevented the short latency of withdrawing an inflamed paw from radiant heat. These results suggest that inflammation differentially increases both NGF and GDNF, which facilitate TRPV1 expression within distinctive neurons to induce thermal hyperalgesia.
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Affiliation(s)
- Fumimasa Amaya
- Department of Anaesthesiology, Kyoto Prefectural University of Medicine, 465 Kajiicho, Kamigyo-ku, Kyoto 602-8566, Japan.
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Abd El-Aleem SA, Morales-Aza BM, McQueen DS, Donaldson LF. Inflammation alters somatostatin mRNA expression in sensory neurons in the rat. Eur J Neurosci 2005; 21:135-41. [PMID: 15654850 DOI: 10.1111/j.1460-9568.2004.03854.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Proinflammatory neuropeptides, such as substance P and calcitonin gene-related peptide, are up-regulated in primary afferent neurons in acute and chronic inflammation. While these neuropeptides have been intensively studied, potentially anti-inflammatory and/or anti-nociceptive neuropeptides such as somatostatin (SS) have been less widely investigated. Endogenous somatostatin is thought to exert a tonic antinociceptive effect. Exogenous SS is anti-inflammatory and antinociceptive and is thought to exert these actions through inhibition of proinflammatory neuropeptide release. In this study we have compared the expression of somatostatin in two inflammatory models: arthritis, a condition associated with increased nociception, and periodontitis, in which there is little evidence of altered nociceptive thresholds. In acute arthritis (< 24 h) SS mRNA was down-regulated in ipsilateral dorsal root ganglia (DRG; 52 +/- 7% of control, P < 0.05), and up-regulated in contralateral DRG (134 +/- 10% of control; P < 0.05). In chronic arthritis (14 days) this pattern of mRNA regulation was reversed, with SS being up-regulated ipsilaterally and down-regulated contralaterally. In chronic mandibular periodontitis (7-10 days), SS mRNA was up-regulated in only the mandibular division of the ipsilateral trigeminal ganglion (TG) (day 7, 219 +/- 9% and day 10, 217 +/- 12% of control; P < 0.02) but showed no change in other divisions of the trigeminal ganglion or in the mesencephalic nucleus. These data show that antinociceptive and anti-inflammatory neuropeptides are also regulated in inflammation. It is possible that the degree of inflammation and nociception seen may depend on the balance of pro- and anti-inflammatory and nociceptive peptide expression in a particular condition.
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Affiliation(s)
- Seham A Abd El-Aleem
- Department of Physiology, University of Bristol School of Medical Sciences, University Walk, Bristol, UK
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Caleo M, Cenni MC. Anterograde transport of neurotrophic factors: possible therapeutic implications. Mol Neurobiol 2004; 29:179-96. [PMID: 15126685 DOI: 10.1385/mn:29:2:179] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2003] [Accepted: 10/06/2003] [Indexed: 12/14/2022]
Abstract
The actions of neurotrophic factors are classically thought to be mediated by their retrograde transport from target tissues to the cell bodies. There is now evidence that specific trophic factors are trafficked anterogradely along peripheral and central axons and released to postsynaptic cells. This review focuses on recent experiments that demonstrate the involvement of the anterograde transfer of neurotrophic factors in various physiological processes, including the regulation of developmental neuronal death, the modulation of synaptic transmission, and the control of axonal and dendritic architecture. The authors also discuss whether anterograde transport of exogenous trophic factors can be exploited to protect damaged postsynaptic neurons and spare their function. This issue has clear implications for possible therapeutic applications of neurotrophic factors.
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Affiliation(s)
- Matteo Caleo
- Istituto di Neuroscienze del CNR and Scuola Normale Superiore, via G. Moruzzi, 1 - 56100 Pisa, Italy.
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Zwick M, Molliver DC, Lindsay J, Fairbanks CA, Sengoku T, Albers KM, Davis BM. Transgenic mice possessing increased numbers of nociceptors do not exhibit increased behavioral sensitivity in models of inflammatory and neuropathic pain. Pain 2004; 106:491-500. [PMID: 14659533 DOI: 10.1016/j.pain.2003.09.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
At least two classes of neciceptors can be distinguished based on their growth factor requirements: glial cell-line derived neurotrophic factor (GDNF)- and nerve growth factor (NGF)-dependent primary afferent neurons. Based on numerous anatomical and biochemical differences, GDNF- and NGF-dependent neurons have been proposed to be involved in the development of different types of persistent pain. To examine this hypothesis we used two lines of transgenic mice that contained a supernormal number of either NGF- or GDNF-dependent neurons (referred to as NGF-OE and GDNF-OE mice, respectively). These mice were tested in a model of inflammatory pain (induced by injection of complete Freund's adjuvant) and neuropathic pain (using a spinal nerve ligation protocol). Contrary to expectations, neither line of transgenic mice became more hyperalgesic following induction of persistent pain. In fact, NGF-OE mice recovered more rapidly and became hypoalgesic despite extensive paw swelling in the inflammatory pain model. In the neuropathic pain model, only wildtype mice became hyperalgesic. Real-time PCR analysis showed that the NGF-OE and GDNF-OE mice exhibited changes in neuronal-specific mRNAs in the dorsal root ganglia but not the spinal cord dorsal horn. These results indicate that increasing the number of nociceptors results in potent compensatory mechanisms that may begin with changes in the sensory neurons themselves.
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Affiliation(s)
- Melissa Zwick
- Department of Anatomy and Neurobiology, University of Kentucky, Lexington, KY 40536, USA Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, University of Pittsburgh, Scaife Hall, Room S-843, 3550 Terrace Street, Pittsburgh, PA 15261, USA Department of Pharmaceutics, Pharmacology, and Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
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Ramer MS, Bradbury EJ, Michael GJ, Lever IJ, McMahon SB. Glial cell line-derived neurotrophic factor increases calcitonin gene-related peptide immunoreactivity in sensory and motoneurons in vivo. Eur J Neurosci 2004; 18:2713-21. [PMID: 14656320 DOI: 10.1111/j.1460-9568.2003.03012.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Calcitonin gene-related peptide (CGRP) is expressed at high levels in roughly 50% of spinal sensory neurons and plays a role in peripheral vasodilation as well as nociceptive signalling in the spinal cord. Spinal motoneurons express low levels of CGRP; motoneuronal CGRP is thought to be involved in end-plate plasticity and to have trophic effects on target muscle cells. As both sensory and motoneurons express receptors for glial cell line-derived neurotrophic factor (GDNF) we sought to determine whether CGRP was regulated by GDNF. Rats were treated intrathecally for 1-3 weeks with recombinant human GDNF or nerve growth factor (NGF) (12 microg/day) and dorsal root ganglia and spinal cords were stained for CGRP. The GDNF treatment not only increased CGRP immunoreactivity in both sensory and motoneurons but also resulted in hypertrophy of both populations. By combined in situ hybridization and immunohistochemistry we found that, in the dorsal root ganglia, CGRP was up-regulated specifically in neurons expressing GDNF but not NGF receptors following GDNF treatment. Despite the increase in CGRP in GDNF-treated rats, there was no increase in thermal or mechanical pain sensitivity, while NGF-treated animals showed significant decreases in pain thresholds. In motoneurons, GDNF increased the overall intensity of CGRP immunoreactivity but did not increase the number of immunopositive cells. As GDNF has been shown to promote the regeneration of both sensory and motor axons, and as CGRP appears to be involved in motoneuronal plasticity, we reason that at least some of the regenerative effects of GDNF are mediated through CGRP up-regulation.
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Affiliation(s)
- Matt S Ramer
- Sensory Function Group, Centre for Neuroscience Research, King's College London, Guy's Campus, London Bridge, London, UK.
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